Norton Ghost is slow. There is Norton Ghost Corporate Edition with multicasting and fast cloning system.
Clonezilla is a free, open source, and multitasking. With DRBL (Diskless Remote Boot in Linux [DRBL] provides a diskless or systemless environment for client machines) and network boot enabled client computers, the only thing you have to prepare is a Clonezilla server. The best thing is ~ you do not even have to prepare a bootable CD or floppy with Partition Image for every client computer.